Lifting device

ABSTRACT

Lift device for lifting or, as the case may be, lowering of a support device ( 2, 3 B,  5 ) of a transport track segment of a transport device for work pieces or the like, which are deposited upon plates, pallets or framework like work piece carriers ( 58 ) and upon which the work piece carrier ( 58 ) is seated translationally displaceably, with a force producing device ( 35, 72, 73 ) for producing a force for lifting or as the case may be lowering the support device ( 2, 3 B,  5 ) and with a force transmission device for transmitting the force from the force producing device to the support device, the force transmission device includes at least one lever ( 25   a,    25   b ), which on one side ( 29   a,    29   b ) is coupled to be essentially horizontally displaceably guided with the force producing device ( 35, 72, 73 ) and on the other side ( 30   a,    30   b ) is coupled with the support device ( 2, 3 B,  5 ) and is guided for essentially vertical displacement.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention concerns a lift device for lifting or, as the casemay be, lowering a support device of a transport track segment uponwhich work piece carriers are provided so as to be translationallydisplaceable.

[0003] 2. Description of the Related Art

[0004] With known flexible transport and assembly systems, a number oftransport tracks or assembly tracks are connected with each other alonga parallel plan, using transverse conveyors provided at right anglesthereto.

[0005] According to the state of the art it is known to use so-calledpush-overs to push the work piece carrier from a transport track onto atransverse conveyor extending at a right angle thereto. A pusher of thistype is comprised of a hydraulic or pneumatic device provided on theside of the track, of which horizontally extending rams push the workpiece or, as the case may be, the carrier from the transport track ontothe transverse conveyor. The problem is the displacement of the workpiece or, as the case may be, the carrier, from the transverse carrieronto the transport track, that is in the reverse direction. It is afurther disadvantage, that the guidance of the work piece or, as thecase may be, the work piece carrier, upon the respective transporttracks or transverse carrier devices is only limitedly possible, sincethis would otherwise impede the pushing-over.

[0006] A further type of (reversible) translation device is known forexample from DE 30 12 355 A1, comprised of transport tracks providedtransverse or parallel to each other. In this device for translation ofwork piece carriers, work pieces, or the like, there is provided in thefree space between the bands of a double belt conveyor band device atranslation device with at least one translation belt extendingperpendicularly to the double belt conveyor belt. This translationdevice has been found advantageous for employment in crossing locationsof conveyor belt devices running perpendicular to each other, and makespossible a problem-free transference of the work piece carrier from onetransport band to another. A problem therewith is that the transportbands or, as the case may be, transport tracks, must be positionedimmediately adjacent to each other.

[0007] From DE 36 01 699 A1 a conveyor device is known, in which thetransverse conveyors simultaneously assume the function of (reversible)translation, wherein a transference from the one track as well also fromthe other longitudinal transport track is made possible thereby. Forthis purpose the transverse conveyor, which crosses the longitudinaltransport track, can be raised and lowered with the aid of a liftingdevice. These lifting devices and similar lifting systems preferablyhave pneumatic or hydraulic assemblies as the lifting device, which havea vertically oriented cylinder and a piston guided therein displaceablein the vertical direction for production of the lift movement, of whichthe piston rod is connected rigidly or via a linkage with the supportdevice which translationally displaceably supports work piece carrier.With this type of vertically moveably guided piston or, as the case maybe, piston rod, high actuation forces are necessary in order to lift thesupport device inclusive of the work piece carrier.

SUMMARY OF THE INVENTION

[0008] The invention is thus concerned with the task, of providing alift device for lifting or, as the case may be, lowering of a supportdevice of a transport track segment, upon which the work piece carriersare placed translationally displaceable, which is so designed, that onlysmall actuation forces are necessary.

[0009] This task is solved in accordance with the invention by a liftingdevice for lifting or, as the case may be, lowering a support device ofa transport track segment of a transport device for work pieces or thelike, upon which plate-, pallet- or frame-shaped work piece carriers arelaid, and upon which the work piece carrier is introducedtranslationally slideable, with a force transmission device including atleast one lever which on one side is coupled to be essentiallyhorizontally displaceably guided with the force producing device and onthe other side is coupled with the support device and is guided foressentially vertical displacement.

[0010] The essential concept of the invention is comprised therein, thata force transmission device is provided, which includes at least onelever, which on the one side is guided at least horizontallydisplaceable and is coupled with the force transmission device and whichon the other side is guided displaceably in the essentially verticaldirection and coupled with the support device. This lever which in thelowered condition of the support device is inclined against thehorizontal, and is then displaced on the other side horizontally forlifting the support device, whereby the other side is lifted, until itfinally in the lift condition of the support device is orientedessentially in the vertical direction. In this position the entire loadof the support device and the work piece carrier provided upon thissupport device inclusive of the work piece situated thereupon rests uponthe lever itself and upon the horizontal guide associated with the onceside of the lever. In this position no actuation force is required fromthe force transmission device in order to maintain the support device inthe raised condition. Also, in the lowered position the forces appliedin the horizontal direction by the force transmission device are lowerthan with a lift device according to the state of the art.

[0011] In a first embodiment of the invention it is envisioned, that theforce transmission device includes two levers, which in parallelarrangement respectively on one end are mounted rotatably on at leastone horizontally slideably guided slide bar and on the other side aremounted on at least one parallel to the slide bar arranged verticallyslideably guided lift bar. This illustrated embodiment has theadvantage, in comparison to a force transmission device based upon asingle lever, that noy only a point-to-point supporting or, as the casemay be, lifting of the support device is possible, but rather that a onedimensional lifting along the lift bar can occur.

[0012] One design of this embodiment envisions, that two slide bars orgibs are provided parallel in such a manner, that these enclose orinclude the two levers. In this manner a two-sided mounting of the leveron the respective slide bars is made possible, so that their stabilitycan be significantly increased.

[0013] In similar manner the stability can be increased when two liftbars are provided in parallel arrangement encompassing the two levers.

[0014] In accordance with the invention a further embodiment isenvisioned, wherein the slider bars are provided with rollers for thehorizontal guidance upon the appropriate guide bars. Therein twoalternatives are possible; on the one hand, that the rollers are mountedrotatably upon the slide bars, and on the other hand, that the rollersare mounted rotatably upon the guide bars. Both alternatives serve toensure the moveability of the slide bar in the horizontal direction.

[0015] A further variation of the invention is comprised therein, thatguide rolls are also provided to the lift bars for vertical guidance atappropriate guide elements. In accordance with the presently describedprinciple, the guide rollers can be provided mounted rotatably upon thelift bars (or an element rigidly connected thereto) or on the respectiveguide elements themselves. Both variants ensure a low friction verticalmoveability of the lift bar and the therewith associated support device.

[0016] In accordance with the invention it is further envisioned, thatsliding blocks are provided, which secure the force transmission devicepreferably in its entirety against a sideways displacement. This means,that these glide blocks are provided in such a manner, that essentiallya linear movement of the slide bars in the horizontal direction is madepossible, as well as a vertical movement of the lift bars. A movement ina direction other than these two movement directions, the planes definedby the vertical movement direction and the horizontal movementdirection, should be prevented by these slide blocks.

[0017] According to the invention it is further envisioned, that theforce-producing device includes at least one pneumatic device or onehydraulic device. These pneumatic or, as the case may be, hydraulicdevices are provided therefore, for producing the horizontaldisplacement movement of the slide bars. The cylinder as well as thetherein guided piston and therewith their piston rod are therebypreferably arranged in horizontal direction, and in particular in thelongitudinal direction of the slider bars. Introduction of parasiticforces are avoided in this mode and manner.

[0018] In similar manner it is also possible to accomplish adisplacement movement with the aid of a linear motor arranged in thejust described manner. Whichever variant is to be employed depends uponthe respective intended use, in particular also from the presence or asthe case may be absence of associated control possibilities.

[0019] A particularly advantageous embodiment of the invention envisionsthat the force transmission device includes at least one (rotation)motor drive, which is coupled with a conversion device for conversion ofthe rotation movement of the motor drive into a horizontal linearmovement. This type of motorized drive is still economical to obtain incomparison to the above described force transmission devices, andassociated devices for conversion or as the case may be translation fora rotation movement into a linear movement are well known in the stateof the art in a variety of alternative embodiments.

[0020] A particular advantageous embodiment is comprised therein, thatan eccentric disk, a cam disk or the like is provided, which can bedriven by the motorized drive and which cooperates with the one side ofthe lever. A cooperation between the eccentric disk and the one side ofthe lever can be realized in particularly simple manner thereby, thatthe eccentric disk (cam disk or the like) carries a pin (cam pin or thelike) arranged eccentric to the drive axis of the motorized drive, whichengages in a linkage mounting provided on one side of the cam, and a pinprovided on one side of the slide bar engages in a linkage mountprovided on the other side of the cam. A system of this type iscomparable with the transmission of force from piston (internalcombustion) motor to the wheel of, for example, an automobile, whereinhowever in the present case the force transmission occurs in theopposite direction.

[0021] In accordance with the invention it is envisioned that themotorized drive is provided with a draw spring, preferably however apressure spring, of which the spring force supports the actuation of the(electric) motor drive, at least during lifting of the support device.The direction of bias of the pressure spring (or for example the drawspring) is thereby preferably arranged just so, that for the running ofthe motor essentially only a half of the force is required, which wouldbe required without the presence of a spring of this type.

[0022] A further embodiment of the invention envisions, that aconnecting device is provided on the other side of the slide bar, whichis rigidly connected with a spring tension device. A pressure spring isseated upon this spring tension device, which for its part on the otherside is seated upon a spring abutment rigidly connected with the guidebar. An arrangement of this type brings about an even force transmissionfrom both sides upon the slide bars.

[0023] In a further inventive embodiment two force transmission devicesin essentially identical form are provided parallel to each other whichrespectively carry segments of an outer roller track or, as the case maybe, an inner roller track of the support device. With an appropriatecoupling it is possible with one level of this embodiment to evenlyraise or lower a preferably associated support device.

BRIEF DESCRIPTION OF THE DRAWING

[0024] Three illustrative embodiments of the invention are shown in thedrawings and will be described in greater detail in the following. Thereis shown:

[0025]FIG. 1 a transport device with multiple longitudinal conveyortracks as well as multiple transverse conveyor tracks as well as aplurality of lift devices for translation of a work piece carrier from alongitudinal tracks to transverse conveyor tracks and the reverse.

[0026] perspective representation

[0027]FIG. 2 a segment from the transport device according to FIG. 1with inventive lift unit and transverse segment.

[0028] perspective representation

[0029]FIG. 3 a first illustrative embodiment of an inventive lift deviceaccording to FIG. 2

[0030] perspective representation

[0031]FIG. 4 the lift action of the inventive lift device according toFIG. 3

[0032] perspective detail view

[0033]FIG. 5 the lift action of the inventive lift device according toFIG. 3

[0034] perspective detail view

[0035]FIG. 6 the lift action of the inventive lift device according toFIG. 3 p1 side view

[0036]FIG. 7 the lift action of the inventive lift device according toFIG. 3

[0037] side view along the plane A-A′ according to FIG. 6

[0038]FIG. 8 the lift action of a second illustrative embodiment of aninventive lift device according to FIG. 2

[0039] view from below

[0040]FIG. 9 the lift action according to FIG. 8

[0041] view from above

[0042]FIG. 10 the lift action according to FIG. 8

[0043] sectional view along the plane B-B′ according to FIG. 8

[0044]FIG. 11 the lift action of a third illustrative embodiment of aninventive lift device according to FIG. 2

[0045] view from below

DETAILED DESCRIPTION OF THE INVENTION

[0046]FIG. 1 shows a transport device 59 with four longitudinal conveyortracks 60 as well as ten transverse conveyor tracks 61. The overalltransport device 59 rests in this example on twenty legs 7, which inthis particular embodiment are provided at the respective crossingpoints of the longitudinal conveyor tracks 60 and the transverseconveyor tracks 61.

[0047] The longitudinal conveyor tracks 60 and transverse conveyortracks 61 respectively exhibit support devices, upon which one or morework piece carriers 58 can be seated translationally displaceable orslideable.

[0048] The support device is comprised in this concrete illustrativeembodiment respectively of two parallel-running roller tracks 2, 3, 52,53, which are comprised of a plurality of sequentially provided supportrollers 51.

[0049] Further, both the longitudinal conveyor tracks 60 as well alsothe transverse conveyor tracks 61 include drive devices, which arecontinuously drivable by a drive motor 4, 54 and can be brought intofrictional contact with the work piece carrier 58. The drive device iscomprised, as will be described in greater detail in the following, of abelt 5, 55 provided between the respective outer lying and inner lyingroller tracks 2, 3 as well as 52 and 53.

[0050] At the respective crossing points, which connect the longitudinalconveyor tracks 60 and transverse conveyor tracks 61 with each other,there are provided in this example respectively one lift device 1. Thislift device 1 serves for the respective raising or as the case may belowering of a transport track segment of the transport device. In theexample the respectively longitudinal conveyor track segments areexclusively lowered.

[0051]FIG. 2 shows the segment from the preceding described transportdevice shown in FIG. 1 and circled with a circular border and indicatedwith X. This segment represents the above described lift device 1 and asection of the transverse conveyor segment 61.

[0052] As can be seen from FIG. 2, the actual lift device 1 rests uponthe support leg 7. As can further be seen from the figure, the rollertracks 52 and 53 of the transverse conveyor track 61 cross the innerlying track 3 of the longitudinal conveyor track 60. Thereby they bridgeover the free space 9 between inner and outer roller track 2, 3 of thelongitudinal conveyor track 60. The inner roller track 3 is therebyinterrupted, so that the free space 56 between the roller tracks 52 and53 of the transverse conveyor track 61 is bridged over by the middleroller track segment 3B of the inner roller track 3. The outer rollertrack segments of the roller track 3 which connect from the outside withthe roller tracks 52 and 53 are referred with reference numbers 3A and3C for purposes of explanation.

[0053] For the translational transport of a work piece carrier 58 guidedtranslationally slideable upon the respective roller tracks 2, 3, 52, 53drive devices are provided in the example for the respective outerroller tracks 2 and 52 of the longitudinal conveyor tracks 60 andtransverse conveyor tracks 61. These drive devices are comprisedrespectively of a drive motor 4 or, as the case may be, 54 and a belt 5or, as the case may be, 55 drivable thereby and guided parallel to therespective roller tracks 2, 52.

[0054] On the basis of FIGS. 3 through 7 there will be described indetail in the following a first illustrative embodiment of an inventivelift device 1. As can be seen from FIG. 3, the support device of thetransport track segment to be raised or as the case may be to be loweredof the transport device 59 for work pieces or the like, which workpieces are placed upon plates, pallets or frame like work piece carriers58, is comprised essentially of two parallel running roller systems, anouter roller track 2 comprised of rollers 51 and an inner roller track 3likewise comprised of rollers 51. On the outer roller track 2 there isengaged an inner lying driven belt 5 engaged in parallel arrangement,which runs over a direction changing roller or the like, which aremounted in profile tracks having perpendicular cross section. As drivemeans in the present example a drive motor is employed.

[0055] The rollers 51 are mounted rotatably close to each other. Thehere not shown work piece carriers 58 lie upon the belt 5 as well asupon the rollers 51 of the parallel and in same elevation providedroller tracks 2 and 3 and are transported with a speed set by theadvancement rate of the belt 5.

[0056] The total assembly of the support device, comprised of the tworoller tracks 2 and 3 (as well as inner roller track comprised in thepresent described manner of the respective roller track segments 3A, 3Band 3C) and the belt 5 driven with the aide of the drive motor 4 restsupon U-shaped angular profiles 47 provided in the same elevation andparallel to each other, which function as carrier 2 a, 3 a, 3 b, 3 c ofthe respective roller track segments 2, 3A, 3B, 3C. The carrier of theouter roller track is referenced in the following with the referencenumber 2 a, the carrier of the outer roller track segment 3A isreferenced with the reference number 3 a, the carrier of the centralroller track segment 3B is referenced with the reference number 3 b andthe carrier of the outer roller track segment 3C is referenced with thereference number 3 c.

[0057] In the present embodiment of the invention essentially the outerroller tracks 2 with the drive unit comprised of drive motor 4 and belt5 as well as the central roller track segments 3B and the respectiveassociated carriers 2 a and 3 b are raiseable (as well again lowerable)relative to the fixed outer roller track segments 3A and 3C. Thelowerability or as the case may be raiseability (verticalmovement/stroke movement) is indicated in the example by the doublearrow referenced with reference symbol V. The coupling between theraiseable roller track segments 2 and 3B is realized by the two paralleloriented beams which also function as spacer 6.

[0058] The overall lift device 1 rests essentially upon the two legs 7which carry a frame comprised of two parallel and in horizontaldirection oriented transverse carriers 8 a and 8 b as well as twoparallel longitudinal carriers 10 a and 10 b which are however orientedperpendicular to the previously mentioned transverse carriers 8 a and 8b.

[0059] This frame, comprised of transverse carriers 8 a and 8 b as wellas the longitudinal carriers 10 a and 10 b, serves on the one handdirectly as rigid carrier for the roller track segments 3 a and 3 c aswell as rigid carrier 52 a and 53 a of the two roller tracks 52 and 53of the transverse conveyor track 61. On the other hand this framecomprised of transverse carriers 8 a and 8 b as well as longitudinalcarriers 10 a and 10 b serves as carrier, against which carriers 2 a and3 b of the outer roller track 2 which are moveable in the verticaldirection, and the center roller track segment 3B are supported.

[0060] In the following on the basis of FIG. 4 through 7 the lift actionof the inventive lift device 1 according to FIG. 3 is described. Thecore of the actual force transmission device of the lift device 1 arethe levers 25 a and 25 b oriented vertically in the raised position ofthe support device. Both levers 25 a and 25 b respectively exhibitlinkages 29 a, 29 b, 30 a and 30 b on their ends. The lower linkages 29a and 29 b are linked with two slider bars 16 a and 16 b oriented in thehorizontal direction on both sides of the lever 25 a and 25 b. On theother end of the lever 25 a and 25 b are linked likewise twohorizontally oriented lift bars 17 a and 17 b linked via the linkage 30a and 30 b in the above described manner.

[0061] The two lower slider bars 16 a and 16 b are guided longitudinallyto be displaceable in the horizontal direction via rollers 22 a and 22 bon guide bars 27 a and 27 b connected rigidly with the longitudinalcarrier 10 a or as the case may be 10 b. This longitudinal slide deviceis referenced in the drawing with a double arrow with the referencecharacter H.

[0062] The lift bars 17 a and 17 b exhibit threaded bores 33 on theirupper side, via which the lift bars 17 a and 17 b (via appropriate bores33 a in the carrier 3 b or as the case may be 2 a of the center rollertrack segment 3B or as the case may be the outer roller track 2 engagingscrews) can be screwed to carriers 2 a or as the case may be 3 b.

[0063] These carriers 3 b of the center roller track segment 3 b as wellas 2 a of the outer roller track 2 exhibit further boreholes 32 a, viawhich the screwing together with two guide elements 13 a and 13 bprovided respectively in spaced relation to the front surface of thelift bars 17 a and 17 b can be accomplished. These guide elements 13 aand 13 b exhibit for this purpose guide boreholes 32 corresponding tothe boreholes 23 a, in which suitable screws can be engaged.

[0064] These guide elements 13 a and 13 b are guided displaceably in thevertical direction on the one hand via guide rollers 22 a and 23 bmounted rigidly on the longitudinal carrier 10 a (or 10 b) as well asvia slide blocks 15 a and 15 b. For reduction of the frictionalresistance there are provided slide pieces 12 a or as the case may be 12b on the respective sides of the guide elements 13 a and 13 b facing theslide blocks 15 a and 15 b, which via balancing springs 14 a, 14 b, 14 cand 14 d press against the sides of the guide element 13 a and 13 bpressing sideways in the horizontal direction against the slide blocks15 a and 15 b provided on the frame profile 11 of a respectivelongitudinal carrier 10 a, 10 b, (FIG. 7).

[0065] The horizontal slideable guidance of the one side of therespective lever 25 a and 25 b with the aid of the slide bars 16 a and16 b as well as the vertical slideability V of the other side of thelever 25 a and 25 b with the aid of the lift bar 25 a and 25 b makes itpossible to convert a horizontal displacement movement into a verticallift movement. If in the concrete case a force transmission device isprovided for example in the horizontal direction against the face of theslide bars 16 a and 16 b, then thereby the lift bars 17 a an 17 b arelifted (or, as the case may be, in the opposite case, they are lowered).The rigid connection of the lift bars 25 a and 25 b with the carriers 2a, 3 b of the corresponding roller tracks 2, 3B with the roller tracks2, 3B to be raised or, as the case may be, to be lowered, brings about araising or as the case may be lowering thereof (vertical movement V) inthe above described manner.

[0066] In the following three different embodiments for production ofthe vertical displacement movement are explained. In particular there isshown in FIGS. 3 through 6 the inventive arrangement of a forceproducing device based upon an electric-motor drive, FIGS. 8 through 10show a appropriate force transmission device based upon two pneumaticunits, and FIG. 11 shows a force transmission unit based upon a singlepneumatic or hydraulic device.

[0067] Reference is made to FIGS. 3 through 6. These force transmissiondevices are based upon a drive motor 35, and a device for converting therotation movement produced by the motor 35 into a horizontal linearmovement H of the slide bars 16 a and 16 b.

[0068] As can be seen from the illustration according to FIG. 5, a drivewheel 31 is seated upon the drive shaft of the motor 35. Via this drivewheel 31 a toothed belt 26 is guided, which again for its part is guidedover a drive wheel 28. This drive wheel 28 is seated upon a drive shaft21, which has the form of a multi-sided profile. This drive shaft 21having multiple sides is rotatably mounted on two mounting blocks orshoes rigidly connected with the two longitudinal carrier 10 a and 10 b.

[0069] On the end of this drive shaft 21 there is seated a crank disk38, which carries an eccentric pin 38 a in eccentric arrangement.

[0070] This eccentric pin 38 a is rotatably guided in a linkage mount 37a of a crank 20. The crank 20 carries on the other end a further linkagemount 37 b, in which a pin 36, which is rotatably mounted in the endface of the slide bars 16 a and 16 b, is likewise rotatably mounted.

[0071] A rotation movement of the motor axle of the motor 35 is thustransmitted to the crank disk 38 via the drive wheel 31, the toothedbelt 26, the drive wheel 28 and the drive shaft 21. The rotatability ofthe crank disk 38 is indicated in the figure by the double arrowreferenced with reference character D.

[0072] The conversion of a force acting in horizontal direction into avertical lift movement and the therewith associated reduction of theforce requirement has already been described above.

[0073] For recognition of the position of the support device theinvention envisions that inductive proximity switches 19 a or as thecase may be 19 b are provided at the direction changing points on theends of the slide bars.

[0074] For reducing the start up torque of the motor 35 the inventionenvisions the following described spring device. Thus there is providedon the other sides of the slide bars 16 a and 16 b a connecting device42, which is rigidly connected with a cylinder like spring tensioningdevice 41, upon which a compression spring 18 is seated on the one sideand which again on the other side is seated upon a rigidly with theguide bar 27 b connected spring abutment 40.

[0075] The entire force transmission is preferably, as can be seen fromthe example of FIG. 5, in doubled parallel arrangement and inessentially identical shape. Both force transmission devices are, as canbe seen from this figure, components of the two longitudinal carriers 10a and 10 b.

[0076] In the following one further inventive embodiment of a forcetransmission device is disclosed. From FIGS. 8 through 10 a device ofthis type can be seen. From the figures one can see a frame like carrier11 as described above. In particular, the two longitudinal carriers 10 aand 10 b as well as the two transverse carriers 8 a and 8 b spaced aparttherefrom are shown. Above this one can see from the figures that theguide bar 27 extends over the entire length of the respectivelongitudinal carrier 10 a or as the case may be 10 b. In this guide bar27 the slide bars 16 a and 16 b exhibiting the rollers 22 a and 22 b areguided displaceably along the horizontal direction. The lift bars 17 arecoupled therewith in the above described mode and manner, which arelikewise guided in the above described mode and manner (however here notillustrated) slideably in the vertical direction V.

[0077] In the present illustrative embodiment the slide bars 16 a and 16b guided in the frame profile 11 of the longitudinal carrier 10 a and 10b are connected with each other via an actuation rod 70.

[0078] In this actuation rod 70 there is provided, mirror symmetricallyto the mirror plane B-B′, securing means 78 and 79, with which rams 74and 75 of two pneumatic devices 72 and 73 are rotatably associated.

[0079] The pneumatic cylinder 72 and 73 of the pneumatic devices areagain associated by means of not in greater detail described securingdevices 76 and 77 to a transverse carrier 8 b.

[0080] The two pneumatic cylinders 72 and 73 are connected by abalancing or equalization valve, which ensures an even pressure actionof both cylinders of the pneumatic devices 72 or as the case may be 73.

[0081] With the aid of these two pneumatic devices 72 and 73 theactuation rod 70 can be displaced in the horizontal direction. Thehorizontal displaceability of the actuating rod and therewith (the notshown) slide bars is indicated as in the previous illustrated embodimentwith the aid of a double arrow, which is provided with the referencecharacter H.

[0082]FIG. 11 shows a lift device 1 based upon a single pneumatic device72. Just as in the illustrative embodiment of a lift device describedabove in detail, so too does the present lift device 1 base itself upona framework like carrier 11, which is comprised of two transversecarriers 8 a and 8 b as well as two longitudinal carriers 10 a and 10 b.Again in the above described mode and manner, slider bars 16 a and 16 bare guided horizontally displaceable in the longitudinal carriers 10 aand 10 b. The slide bars 16 a and 16 b guided in the respectivelongitudinal carriers 10 a and 10 b are connected with each other via anactuating rod 70. The actuating rod 70, just as in the previous example,passes through a right angle shaped recess 80 in the inner lying shankof the U-shaped longitudinal carrier 10 a and 10 b.

[0083] In contrast to the above described embodiment, the displacementof the actuating rod 70 occurs with the aid of a single pneumatic device74 provided in the center of the actuating rod 70, oriented in thehorizontal direction. The securing of the pneumatic cylinder 72 as wellas the force transmitting rams 74 occurs analogously to the previouslydescribed embodiments with the aid of suitable securing means 78 and 76.

REFERENCE NUMBER LIST

[0084] 1 Lift device

[0085] 2 Outer roller track

[0086] 2a Carrier for the outer roller track

[0087] 3 Inner roller track

[0088] 3a Carrier for the outer roller track segment

[0089] 3b Carrier for the center roller track segment

[0090] 3c Carrier for the outer roller track segment

[0091] 3a Outer roller track segment

[0092] 3b Center roller track segment

[0093] 3c Outer roller track segment

[0094] 4 Drive motor

[0095] 5 Belt

[0096] 6 Spacer

[0097] 7 Leg

[0098] 8a Transverse carrier

[0099] 8b Transverse carrier

[0100] 9 Free space

[0101] 10 Longitudinal carrier

[0102] 10a Longitudinal carrier

[0103] 10b Longitudinal carrier

[0104] 11 Frame profile

[0105] 12a Slide piece

[0106] 12b Slide piece

[0107] 13a Guide element

[0108] 13b Guide element

[0109] 14a Equalizing ring

[0110] 14b Equalizing ring

[0111] 14c Equalizing ring

[0112] 14d Equalizing ring

[0113] 15a Slide block

[0114] 15b Slide block

[0115] 16a Slide bar

[0116] 16b Slide bar

[0117] 17 Lift bar

[0118] 17a Lift bar

[0119] 17b Lift bar

[0120] 18 Compression spring

[0121] 19a Inductive proximity switch

[0122] 19b Inductive proximity switch

[0123] 20 Crank

[0124] 21 Drive shaft

[0125] 22a Rollers for horizontal guidance

[0126] 22b Rollers for horizontal guidance

[0127] 23a Guide rollers for vertical guidance

[0128] 23b Guide rollers for vertical guidance

[0129] 24 Mounting block or shoe

[0130] 25a Lever

[0131] 25b Lever

[0132] 26 Toothed belt

[0133] 27 Guide bar

[0134] 27a Guide bar

[0135] 27b Guide bar

[0136] 28 Drive wheel

[0137] 29a Linkage

[0138] 29b Linkage

[0139] 30a Linkage

[0140] 30b Linkage

[0141] 31 Drive wheel

[0142] 32 Threaded borehole

[0143] 32a Borehole

[0144] 33 Threaded borehole

[0145] 33a Borehole

[0146] 34 Threaded borehole

[0147] 34a Borehole

[0148] 35 Motor

[0149] 36 Pin

[0150] 37a Linkage mount

[0151] 37b Linkage mount

[0152] 38 Crank disk/eccentric disk

[0153] 38a Eccentric pin

[0154] 39 Drive wheel

[0155] 40 Spring abutment

[0156] 41 Spring tension device

[0157] 42 Connecting device for connecting spring tension device withslide bar

[0158] 47 U-shaped angular profile

[0159] 51 Roll

[0160] 52 Outer roller track

[0161] 52a Carrier for outer roller track

[0162] 53 Inner roller track

[0163]53a Carrier for the inner roller track

[0164] 54 Drive motor

[0165] 55 Belt

[0166] 56 Free space

[0167] 58 Work piece carrier

[0168] 59 Transport device

[0169] 60 Longitudinal conveyor segment

[0170] 61 Transverse carrier segment

[0171] 70 Actuation rod valve

[0172] 71 Pneumatic device

[0173] 73 Pneumatic device

[0174] 74 Ram

[0175] 75 Ram

[0176] 76 Securing device

[0177] 77 Securing device

[0178] 78 Securing device

[0179] 79 Securing device

[0180] 80 Recess

[0181] 81 Recess

[0182] V Vertical movement/stroke movement

[0183] H Horizontal movement/displacement movement

[0184] D Rotational movement

[0185] S Tolerance

What is claimed is:
 1. Lift device for lifting and lowering of a supportdevice (2, 3B, 5) of a transport track segment of a transport device forwork pieces or the like, which work pieces are deposited upon plate-,pallet- or framework-like work piece carriers (58), and upon which thework piece carriers (58) are seated translationally displaceable with aforce producing device (35, 72, 73) for producing a force for lifting orlowering the support device (2, 3B, 5) and with a force transmissiondevice for transmitting the force from the force producing device to thesupport device thereby characterized, that the force transmission deviceincludes at least one lever (25 a, 25 b), which on one side (29 a, 29 b)is coupled to be essentially horizontally displaceably guided with theforce producing device (35, 72, 73) and on the other side (30 a, 30 b)is coupled with the support device (2, 3B, 5) and is guided foressentially vertical displacement.
 2. Lift device according to claim 1,thereby characterized, that the force transmission device includes twolevers (25 a, 25 b), which are rotatably mounted (29 a, 29 b) inparallel arrangement respectively on one end to at least one slide bar(16 a, 16 b) guided for horizontal displacement and on the other end arerotatably mounted (29 a, 29 b) to at least one lift bar (17 a, 17 b)guided for vertical displacement parallel to the slide bar (16 a, 16 b).3. Lift device according to claim 2, thereby characterized, that twoslide bars (16 a, 16 b) are provided oriented parallel and bracketingthe two levers (25 a, 25 b).
 4. Lift device according to claim 2 or 3,thereby characterized, that two lift bars (17 a, 17 b) are provided inparallel orientation and bracketing the two levers (25 a, 25 b).
 5. Liftdevice according to one of the claims 2-4, thereby characterized, thatthe slide bars (16 a, 16 b) are associated with rollers (22 a, 22 b) forhorizontal guidance on suitable guide bars (27, 27 a, 27 b).
 6. Liftdevice according to claim 5, thereby characterized, that the rollers (22a, 22 b) are mounted rotatably in the slide bars (16 a, 16 b).
 7. Liftdevice according to claim 5 or 6, thereby characterized, that therollers are mounted rotatably in the guide bars.
 8. Lift deviceaccording to one of claims 2 through 7, thereby characterized, that thelift bars (17 a, 17 b) are provided with guide rollers (22 a, 22 b) forvertical guidance on suitable guide elements (13 a, 13 b).
 9. Liftdevice according to claim 8, thereby characterized, that the guideelements (13 a, 13 b) are connected essentially rigidly with the liftbars (17 a, 17 b).
 10. Lift device according to one of the precedingclaims, thereby characterized, that slide blocks (15 a, 15 b ) areprovided for guiding the force transmission device (16 a, 16 b, 17 a, 17b, 25 a, 25 b) in the sideways direction.
 11. Lift device according toone of the preceding claims, thereby characterized, that the forcetransmission device includes at least one pneumatic device (72, 73). 12.Lift device according to one of the preceding claims, therebycharacterized, that the force transmission device includes at least onehydraulic device.
 13. Lift device according to one of the precedingclaims, thereby characterized, that the force transmission deviceincludes a linear motor.
 14. Lift device according to one of thepreceding claims, thereby characterized, that the force transmissiondevice includes at least one (rotation-) motor drive (35) and aconversion device for converting the rotational movement of the motordrive (35) into a horizontal linear movement.
 15. Lift device accordingto claim 14, thereby characterized, that an eccentric disk, a crank disk(38) or the like is provided, which is driveable by a motor drive (35)and which is in operable association with one end (29 a, 29 b) of thelever (25 a, 25 b).
 16. Lift device according to claim 15, therebycharacterized, that the eccentric disk, the crank disk (38) or the likecarries an eccentric pin, crank pin (38 a) or the like eccentric to thedrive axis of the motor drive (35), which engages in a linkage mount (37a) provided on the one side of a crank (20), wherein a pin (36) providedon the one side of the slide bar(s) (16 a, 16 b) engages in a linkagemount (37 b) provided on the other side of the crank (20).
 17. Liftdevice according to one of the preceding claims 14 through 16, therebycharacterized, that the motor drive (35) is provided with a pressure orpull spring (18), of which the spring effect supports the start-up ofthe motor drive (35) at least during lifting of the support device (2,3B, 5).
 18. Lift device according to claim 17, thereby characterized,that a connecting device (42) is provided on the other side of the slidebar(s) (16 a, 16 b), which is rigidly connected with a spring tensioningdevice (41), upon which a pressure spring (18) is seated on one end andwhich on the other side is seated upon a spring abutment (40) rigidlyconnected with the guide bar (27 b).
 19. Lift device according to one ofthe preceding claims, thereby characterized, that two force transmissiondevices (16 a, 16 b, 17 a, 17 b, 25 a, 25 b, 18, 20) are provided inessentially identical form in parallel arrangement to each other, whichrespectively carry segments of an outer roller track (2) or an innerroller track (3B) of the support device.